[TenTec] balanced antenna tuner ( or how to do things on the cheap - tribute to Geoff's drive for cost effect

[Dr. Gerald N. Johnson]

On Wed, 2008-04-30 at 08:44 +0000, Marinus Loewensteijn wrote:
> Geoff
>  
> In your drive for equipment on the cheap I like to draw your attention to the S-Match as promoted by PA0FRI: http://www.xs4all.nl/~pa0fri/ATU/Smatch/smatcheng.htm
>  
> It uses only three components, tunes very easily and can handle both balanced as unbalanced antennas. Unfortunately you may have to build a different version for 160m than for 10m because minimum capacitance values do have an impact.
>  
> It should be the ideal beginner's project, in particular if I see prices asked for "commercial" antenna tuners and which often contribute a considerable expense towards establishing a station. 
>  
> By the way - even with the older tentec gear like the Omni-C one does not need a SWR meter since that is already built in to the rig. (And "standalone" SWR meter's  prices are through the roof for such a simple piece of equipment)
>  
> Enjoy, 73, Marinus, ZL2ML


Over the decades, I've had good performance from the SWR bridges with
the coupling wire threaded under the braid of a length of coax. Costs a
box and connectors, a length of coax sans jacket, a bit of enameled
wire, a diode or two. I've used VOM or VTVM as the indicator most of the
time, but there are low cost meters available at surplus places like
Dan's Small Parts (who also sells radio kits).

And couplers can be built with a toroid to be much more compact that the
coax style. I prefer Bruene's circuit to W1FB's circuit.

73, Jerry, K0CQ